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Gravity feed boiler/ american standard model#g27dpgc

This is a really old boiler and I would like to know why is the pressure relief valve keep discharging water? I replaced the expansion tank and the pressure relief valve and it is still discharging water.. The only thing that I did was see if the pressure relief valve was working, after that I was unable to keep the make up water on, so now I just go down stairs everyday to make sure the boiler has enough water..

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Re: gravity feed boiler/ american standard model#g27dpgc

Your make up water pressure is greater than the safety relief pressure. The safety should be 30psi lift. the makup usually goes through a regulator called an automatic makeup valve. these valves operate infrequently on a closed system and get rusty. They stick. If yours is stuck open, then your makeup water pressure which is probably greater than 30psi is overpressuring your boiler.

Posted on Sep 30, 2008

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Re: gravity feed boiler/ american standard model#g27dpgc - Air Conditioners

Change valve

Posted on Mar 17, 2008

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